1. Field of the Invention
The invention relates to a data communication system, data decoding apparatus and method therefor, which transmit transmission objective data in association with a symbol indicating a subset of plural carrier waves in groups of a predetermined number of bits.
2. Description of the Related Art
For example, Y. Hou and M. Hamamura, “A novel modulation with Parallel combinatory and high compaction multi-carrier modulation”, IEICE Trans. Fundamentals, vol. 90, no. 11, pp. 2556-2567, November 2007 (which will be called Non-Patent Document 1) discloses a PC/HC-MCM (high compaction multi-carrier modulation) applying PC to high definition multi-carrier modulation (HC-MCM).
However, Non-Patent Document 1 does not disclose a method that decodes, by two-level decoding, a transmit signal acquired by multi-carrier modulation.
In other words, Non-Patent Document 1 does not disclose the configuration including performing first decoding including maximum likelihood decoding for decoding in small groups at a time sequentially plural times on the data included in a sample acquired from a transmit signal, finally decoding all data, performing second decoding including maximum likelihood decoding on all or partial data patterns imaginable from the result of the first decoding and decoding the data only if it is decided that the result of the first decoding contains an error.